1. Field of the Invention
This invention relates to an exposure system, and more particularly to an exposure system for exposing a color photosensitive material containing therein a silver-salt photosensitive material by the use of an organic EL element which emits color light.
2. Description of the Related Art
There has been known an exposure system where a photosensitive body is two-dimensionally exposed and an image is recorded on the photosensitive body by exposing the photosensitive body to light emitted from a light emitting element array comprising a plurality of light emitting elements arranged in the main scanning direction while the light emitting element array and the photosensitive body are moved relatively to each other. Recently, various exposure systems in which an organic EL (electroluminescence) element is employed as the light emitting element have been proposed.
Further, in U.S. patent Laid-Open No. 20010052926, there is disclosed an example of an exposure system where a photosensitive body formed of, e.g., a silver-salt photosensitive material is recorded with a full color image by the use of a red organic EL element, a green organic EL element and a blue organic EL element which respectively emit light in a red region, light in a green region and light in a blue region.
In the conventional exposure systems where organic EL elements are employed to expose the color photosensitive body, there has been a problem that it is apt to cause color mixing and deteriorates in color reproduction. The reasons will be described in detail, hereinbelow.
In FIG. 4, curve a shows sensitivity spectrum of a typical red silver-salt photosensitive material which produces cyan and curve b shows a light emitting spectrum of a typical blue organic EL element. As can be seen from the curve a, red silver-salt photosensitive materials generally have a sensitivity in a short wavelength region not longer than about 500 nm with a peak near 380 nm or so as well as a sensitivity in a red region with a peak about 700 nm. Whereas, the light emitting spectrum of a blue organic EL element which is now available has a skirt extending into the short wavelength side. Since the skirt of the light emitting spectrum largely overlaps with the sensitivity range not longer than about 500 nm of the red silver-salt photosensitive materials, the red silver-salt photosensitive materials easily sense light upon emission of light by a blue organic EL element.